<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
<style type="text/css">
#p1 {font-weight: lighter;}
#p2 {font-weight: normal;}
#p3 {font-weight:bold; }
#p4 {font-weight :bolder;}
</style>
</head>
<body>
    <p id="p1">字体粗細为:1ighter</p >
        <p id="p2">字体粗细为:normal</p >
            <P id="p3">字体相细为:bold</p>
                <P id="p4">字体粗细为:bolder </p >
    </body>
     </html>
